Gelatinized propellent explosive and process of preparing same



UNITED STATES PATENT OFFICE.

FREDERIC LEWIS NATHAN AND WILLIAM RINTOUL, OF STEVENSTON, AND FRANK BAKER, DECEASED, LATE OF STEVENSTON, SCOTLAND, BY HENRY BAKER, 0F ETON, WINDSOR, ENGLAND, ADMINISTRATOR OF SAID FRANK BAKER, ASSIGNORS TO NOBELS EXPLOSIVES COMPANY, LIMITED, OF GLASGOW, SCOTLAND.

GELATINIZED PROPELLENT EXPLOSIVE AND PROCESS OF PREPARING SAME.

Specification of Letters Patent.

Patented May 4, 1920.

No Drawing. Application filed February 26, 1914, Serial No. 821,338. Renewed October 21, 1918. Serial T 0 all whom it may concern:

Be it known that Colonel Sir FREDERIC LEWIS NATHAN and VILLIAM BIN'roUL, both subjects of the King of Great Britain and Ireland, and residing at Ardeer, Stevenston, Ayrshire, Scotland, and FRANK BAKER, deceased, late of Ardeer, Stevenston, Ayrshire, Scotland, invented a certain new and useful Gelatinized Propellent Explosive and Processof Preparing Same, of which the following is a specification.

This invention relates to gelatinized propellent explosives.

Such explosives at the present day are generally prepared by gelatinizing nitrocellulose, with or without nitroglycerin by a volatile solvent but this has many disadvantages chiefly residing in the slowness of the drying operation adopted for expelling the solvent from the gelatinized mass, in the impairment of the stability of the material due to the heating and in the changes consequent on slow after-drying during storage.-

In the course of investigations having for their object to discover improved stabilizers for nitric ester explosives we have found that among the groups of bodies ascertained to be good stabilizers-certain anilids, aromatic-radical-containing substituted carbaminic acid, esters, aromatic-radical-containing partially substituted ureas, and aromatic-radical-containing simple or mixed others (see applications Serial No. 771,621, filed June 4, 1913, Patent No. 1,090,642 granted March17, 1914; Serial No. 771,623 filed June 4. 1913, Patent No. 1,090,644 granted March 17 1914; Serial No. 771,620 filed June 4, 1913, Patent No. 1,090,641

anted March 17, 1914; Serial No. 771,622 Sled June 4, 1913, Patent No. 1,090,643, granted March 17, 1914.)are a number which are also good gelatinizers for nitrocellulose so that by using them both gelatinization, without the above inconveniences, and stabilization can be obtained.

We have now further found however that satisfactory results" can be attained without necessarily using a substance which of itself performs these two functions and that provided certain conditions are complied with a gelatinized ropellent explosive can be so obtained whic can be prepared without the inconveniences in working with a volatile solvent and of good chemical and physical stability.

The conditions in question are that in the first place the gelatinizing agent shall be sufiiciently soluble in nitroglycerin to remain dissolved in product, secondly that a stabilizing agent must be present which shall be capable of taking up the products of the inevitable slow decomposition of such explosives however carefully prepared and thirdly that these bodies must be such that neither singly nor when present together or when acted upon by the products of slow decomposition do they act to accelerate this decomposition.

It has been found that the neglect of any one of these conditions is sufiicient to render the product an unsatisfactory onesegregation and change in both composition and ballistics accompanying insufficient solubility of the gelatinizer in the nitroglycerin; the accelerating effect of the products of slow decomposition upon the further decomposition of the material when they are allowed to remain in contact with the material and not disposed of by a stabilizer being such as to render the material inserviceable and often dangerous and the presence of an unsuitable radical or group in the stabilizing or gelatinizing compounds used or those formed from them with the products of decomposition during storage readily leading to series reduction in the stability of the explosive.

According to this invention therefore gelatinized propellent explosives are prepared from nitrocellulose and nitroglycerin by incorporating with them a gelatinizing agent and a stabilizing agent of the character in question.

In carrying the invention out in one way the following ingredients, namely 40 parts of nitroglycerin, parts of soluble nitrocellulose, 7.5 parts of para-nitro-methylacetanilid (the gelatinizer) and 2.5 parts of ethyl-(fi-naphthyl-ether the stabilizer) are brought together by t e wet suspension method of Lundholm, English Patent No.

10376 of 1889, the gelatinous-mass separating from the aqueous sus enslon of the materials being freed as at as possible from water by pressing and rolling between rollers heated to from 40 C. to 50 0., then gelatinized by rollin at a temperature of from 50 C. to 0. and the sheet so obtained cut into flakes or strips or pressed into any desired form by a pressure of several hundred atmospheres applied to it at a temperature of from 50 to 7 0 C.

This example is one in which the gelatinizer is a body falling within the classes first above referred to as furnishing good gelatinizers but which owing to the presence of an unsuitable group in it is not possessed of satisfactory stabilizing properties and so excluded from use for that purpose, and in this example this is compensated by using a body of another of these classes, an ether, to give the stabilizing effect.

At the same time while the classes of bodies referred to do in this way furnish good gelatinizers a wide variety of other materials sufficiently soluble in nitro-glycerin (say to the extent of about 25% at least at ordinary temperatures) and complying with the other conditions isavailable of which amyl phthalate, ethyl phthalate, mono-, dior tri-acetin, and nitro derivatives of aromatic hydrocarbons such as diand trinitrotoluene are instances.

Again the stabilizer need not fall within the classes first considered provided it satisfies the requirements indicated and preferably is soluble to the extent of not less than 5% in nitroglycerin and phenanthrene (see Spica, Zez't. f. Schz'essmwl Sprengstofi- 'wesen 1912 p. 129) is an instance of such a body. Our experience has shown us that stabilizers soluble in nitroglycerin tend to increase in solubility in admixture of nitroglycerin and gelatinizer.

Examples of suitable mixtures are (a) 40 parts nitroglycerin, 50 parts soluble nitrocellulose (12.6% nitrogen) 7.5 parts ethylphthalate as gelatinizer and 2.5 parts ethyl-{i-naphthyl ether as stabilizer.

(7)) 40 parts nitroglycerin, 50 parts soluble nitrocellulose, 7.5 parts ethyl phthalate and 2.5 parts phenyl-benzyl ether.

(0) 40 parts nitroglycerin, 50 parts soluble nitrocellulose. 7.5 parts para-nitromethyl acetanilid and 2.5 parts phenanthrene.

Where the wet incorporation method is used and the substances to be employed as gelatinizer and stabilizer are soluble in water it is preferable to use as the suspending liquid a solution of these bodies in water and of such a concentration that the resulting paste will have the desired composition.

We claim:

1. The process which comprises mixing together nitro-cellulose, nitroglycerin, paranitro-methyl-acetanilid, and a stabilizing substance soluble in the mixture of these ingredients and then gelatinizing the mixture.

2. The process which comprises mixing together nitrocellulose, nitroglycerin, paranitro-methyl-acetanilid and a stabilizing substance soluble in the mixture of these ingredients, said substance being a readily nitratable aromatic radical containing compound, and then gelatinizing the mixture.

3. A propellent explosive comprising a and a stabilizing substance soluble in the mixture comprising the previously mentioned constituents, said substance being a readily nitratable aromatic radical containing compound.

5. A propellent explosive comprising a gelatinous admixture of about 50 parts of soluble nitrocellulose, about 40 parts of nitroglycerin, about 7.5 parts of para-nitromethyl acet-anilid and about 2.5 parts phenanthrene.

6. A propellent explosive comprising a gelatinized admixture of soluble nitrocellulose, nitroglycerin and para-methyl-acetanilid.

7. A propellent explosive comprisin a gelatinized admixture of soluble nitroce lulose, nitroglycerin, para-nitro-methyl-acetanilid, and phenanthrene.

8. The process which comprises mixing together nitrocellulose, nitro-glycerin, a non-volatile gelatinizing agent sufliciently soluble in the nitro-glycerin to remain dis.- solved in the mixture, and a stabilizing agent capable of taking up any products of decomposition, and which will not accelerate decomposition in the presence of the other constituents, and then gelatinizing the mixture.

9. The process which comprises mixing together nitrocellulose, nitro-glycerin, a non-volatile aromatic gelatinizlng compound sufliciently soluble in the nitro-glycerin to remain dissolved in the mixture, and a stabilizing agent capable of taking up any products of decomposition, and which will not accelerate decomposition in the presence of theother constituents, and then gelatinizing the mixture.

10. The process which comprises mixing together nitrocellulose, nitro-glycerin, a non-volatile gelatinizing ag'ent sufliciently soluble in the nitro-glycerin to remain dissolved in the mixture, and an aromatic stabilizing compound capable of taking up any products of decomposition, and which will not accelerate decomposition in the presence of the other constituents, and then gelatinizing the mixture.-

11; The process which comprises mixing together nitrocellulose, nitro-glycerin, a non-volatile aromatic gelatinizing compound sufiiciently soluble in the nitro-glycerin to remain dissolved in the mixture, and an aromatic stabilizing compound capable of taking up any products of decomposition, and which will not accelerate decomposition in the presence of the other constituents, and then gelatinizing the mixture.

12. A propellent explosive comprising a gelatinous admixture of nitrocellulose, nitro-glycerin, a non-volatile gelatinizing agent sufliciently soluble in the nitro-glycerin to remain dissolved in the mixture, and a stabilizing agent capable of taking up any products of decomposition, and which Will not accelerate decomposition in the presence of the other constituents.

13. A propellent explosive comprising a gelatinous admixture of nitrocellulose, nitro-glycerin, a non-volatile aromatic gelatinizing compound sufliciently soluble in the nitro-glycerin to remain dissolved in the mixture, and a stabilizing agent capable of taking up any products of decomposition, and which will not accelerate decomposition in the presence of the other constituents. V

14. A propellent explosive comprising a gelatinous admixture of nitrocellulose, nitro-glycerin, a non-volatile gelatinizing agent sufficiently soluble in the nitro-glycerin to remain dissolved in the mixture, and an aromatic stabilizing compound capable of taking up any products of decomposition, and which will not accelerate decomposition in the presence of the other constituents. g

15. A propellent explosive comprising a gelatinous admixture of nitrocellulose, nitro-glycerin, a non-volatile aromatic gelatinizing compound sufliciently soluble in the nitro-glycerin to remain dissolved in the mixture, and an aromatic stabilizing compound capable of taking up any products of decomposition, and which will not acceleratedecomposition in the presence of the other constituents. V

19 A propellent explosive comprising a gelatinous admixture of nitrocellulose, nitroglycerin, a non-volatile gelatinizing agent sufliciently soluble in the nitro-glycerin to remain dissolved in the mixture, and a stabilizing agent soluble in the mixture capable of taking up any products of decomposition, and which will not accelerate decomposition in the presence of the other constituents 17. A propellent explosive comprising 'a gelatinous admixture of nitrocellulose, nitroglycerin, a non-volatile aromatic gelatinizing compound sufficiently soluble in the --nitro-glycerin to remain dissolved in the mixture, and a stabilizin agent soluble in the mixture capable of taliing up any products of decomposition, and which will not accelerate decomposition in the presence of the other constituents.

18. A propellent explosive comprising a gelatinous admixture of nitrocellulose, nitroglycerin,a non-volatile gelatinizing agent sufficiently soluble in the nitro-glycerin to remain dissolved in the mixture, and an aromatic stabilizing compound soluble in the mixture capable of taking up any products of decomposition, and which will not accelerate decomposition in the presence of the other constituents.

19. A propellent explosive comprising a gelatinous admixture of nitrocellulose, nitroglycerin, a non-volatile aromatic gelatinizing compound sufliciently soluble in the nitro-glycerin to remain dissolved in the mixture, and an aromatic stabilizing compound soluble in the mixture capable of tak-- mg up any products of decomposition, and Which will not accelerate decomposition in the presence of the other constituents.

20. A propellent explosive comprising a gelatinous admixture of a relatively large amount of nitrocellulose, a relatively large amount of nitro-glycerin, and relatively small amounts of a non-volatile substance capable of gelatinizing nitrocellulose and a non-volatile stabilizer capable of absorbing the products of slow decomposition of such nitric esters during storage, the admixed substances being soluble to such an extent in nitroglycerin as to insure substantial homogeneity in the final explosive and being free from the property of accelerating decomposition of the constituents present.

21. A propellent explosive consisting of at least about 40 parts of nitroglycerin, relatively small amounts of a non-volatile substance capable of gelatinizing nitrocellulose and a non-volatile stabilizer capable of absorbing the products of slow decomposition of such nitric esters during storage, the balance of 100 parts being mainly nitrocellulose, the gelatinizer and stabilizer being soluble to such an extent in nitro-glycerin as to insure substantial homogeneity in the final explosive and free from the property of accelerating decomposition of the constituents present.

22. A propellent explosive comprising a gelatinous admixture-of a relatively large amount of nitrocellulose, a relatively large amount of nitro-glycerin and relatively small amounts of a non-volatile substance capable of gelatinizing nitrocellulose and a non-volatile stabilizer capable of absorbing the products of slow decomposition of such nitric esters during storage, the gelatinizer and stabilizer being soluble to such an ex tent in nitro-glycerin as to insure substantial homogene1ty in the final explosive and free from the property of accelerating the decomposition of the constituents present,

at least one of the two substances added in small amount being areadily nitratable aromatic-radical-containing compound.

23. A propellent explosive consisting of at least about 40 parts of nitroglycerin, relatively small amounts of a non-volatile substance capable of gelatinizing nitrocellulose and a non-volatile stabilizer capable of absorbing the products of slow decomposition of such nitric esters during storage, the balance of 100 parts being mainly nitrocellulose, the gelatinizer and stabilizer being soluble to such an extent in nitro-glycerin as to insure substantial homogeneity in the final explosive and free from the property of accelerating decomposition of the constituents present, at least one of the two substances added in small amount being a. readily nitratable aromatic-radicalcontaining compound.

24. A propellent explosive consisting of at least about 40 parts of nitro-glycerin, a non-volatile substance, capable of gelatinizing nitrocellulose and a. non-volatile stabilizer capable of absorbing the products of slow decomposition of such nitric esters during storage, the balance of 100 parts being mainly nitrocellulose, the gelatinizer and stabilizer being soluble to such an extent in nitro-glycerin as to insure substantial homogeneity in the final explosive and free from the property of accelerating decomposition of the constituents present.

25. A propellent explosive consisting of at least about 40 parts of nitro-glycerin, a non-volatile substance, capable of gelatinizing nitrocellulose and a non-volatile stabilizer capable of absorbing the products of slow decomposition of such nitric esters during storage, the balance of 100 parts being mainly nitrocellulose, the gelatinizer and stabilizer being soluble to such an extent in nitro-glycerin as to insure substantial homogeneity in the final explosive and free from the property of accelerating decomposition of the constituents present, at least one of the tWo last mentioned substances being a readily nitratable aromatic-radical-containing compound.

26. A propellent explosive comprising a gelatinous admixture of soluble nitrocellulose, nitro-glycerin, a gelatinizer and phenanthrene.

In testimony whereof we have signed our names to this specificatlon 1n the presence of two subscriblng Witnesses.

FREDERIC LEWIS NATHAN.

WILLIAM RINTOUL. WVitnesses:

M. B. NIoHOL,

ALEX FORBES.

1 HENRY BAKER, Administrator of the estate of F rank Baker,

deceased. Witnesses:

P. A. OSMTHWAITE, BERTRAM H. MATTHEWS. 

